A VOD system is a general term for a communication network service in which video information is instantaneously provided to a user upon the request of the user. The elementary structure of a VOD service system is illustrated in FIG. 1.
Specifically, the VOD service system contains a server 10, a network 12, and a terminal device 14. The server 10 provides image data to the network 12 in response to a command received from a user, and the network 12 transmits the image data to the terminal device 14. The device 14 restores and reproduces the image data so that it can be perceived by the user.
In order to generate a command from a user, the terminal device 14 receives menu data from the server 10 via the network 12 and displays various menus. Then, the user can select options from the menus, and in turn, the device 14 requests additional menu data to be supplied from the server 10. Thus, by selecting the appropriate options on the menus, the user can navigate to a desired service screen.
On the other hand, the user may display a desired service screen without navigating through a series of menus. Specifically, if the user knows a direct code which identifies the desired service screen, the user can directly obtain the service screen by entering the code.
If the terminal device 14 is instructed by the user to receive menu data from the network 12 or server 10 in order to navigate to a desired service screen, the device 14 must continuously receive menu data and display various menus until the desired service screen is found. Thus, if the menu data contains a large amount of graphics oriented data, the amount of service delay significantly increases, and thus, the time required to be connected to the network 12 likewise increases. Accordingly, the connect-time fees incurred by the user escalate, and the cost of receiving the desired service screen becomes less affordable.
However, if a direct code is input by the user to immediately display the desired service screen, the amount of time necessary to be connected to the network 12 decreases. However, the user must remember which direct code corresponds with which service screen and must maintain a list of codes for newly added services. Consequently, relying on direct codes for accessing the service screens is inconvenient.
In some systems, direct codes for various service screens may be displayed in various menus to allow the user to easily identify the direct code. However, there is a limit to the number of codes which can be shown. Moreover, even if all of the direct codes for all of the service screens which can be potentially accessed from the currently displayed menu are shown in the menu, an apparatus is required to search for the direct codes when a menu is displayed. Accordingly, the navigator becomes complicated, and the service provided by the system is deteriorated.